Hello Pankaj,
The unused column in the admin UI indicates roles that a user has not utilized in the last 30 days. The unused column data is not real time it updates every 48 hours. This data is based on the last 30 days of usage patterns.
Unfortunately there is currently no direct API endpoint to retrieve the "unused" column information. This data is only visible through the Admin UI.
Cheers,
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Cameron
Online Community Manager/Moderator
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